Bristol-Myers Squibb Co. reported results from a phase 1/2 clinical trial looking at the company's blockbuster cancer drug Opdivo in patients with human papillomavirus (HPV)-associated cancers premarket Friday. The clinical trial enrolled 24 patients with advanced cervical, vaginal and vulval cancers, with responses only seen in the trial's 19 cervical cancer patients. Preliminary results include an objective response rate of 20.8% and, for women experiencing complete or partial response or stable disease, there was a 70.8% disease control rate, the company said. The trial outcome, which will be presented by the company today at the American Society of Clinical Oncology annual meeting, "supports further investigation, especially because these patients have very limited options after chemotherapy or radiation fails," said Dr. Shinta Cheng, development lead at Bristol-Myers. Bristol-Myers shares were not active in premarket trade. Shares have dropped 4.1% over the last three months, compared with a 2% rise in the S&P 500 .